Support for refractory blocks



Oct. 24 1967 v H E 3,348,930

SUPPORT FOR REFRACTORY BLOCKS Filed May 6, 1965 ATTORNEYS United States Patent Office 3,348,930 Patented Oct. 24, 1967 3,348,930 SUPPGRT F OR REFRACTORY BLOCKS George E. Fisher, Cherry Lane, Ambler, Pa. 19002 Filed May 6, 1965, Ser. No. 453,779 8 Claims. (Cl. 29-183) This invention relates to heating equipment of the kind having uninsulated electrical resistance or heating elements supported by refractory blocks. By heating equipment is meant furnaces, ovens, kettles, melting pots, jackets and the like.

More specifically, the invention relates to an improved support for the refractory blocks, the support having special structure which enables the same to be used either in equipment having flat walls or in equipment having curved walls.

One of the principal objectives of the invention is to provide a support structure which can be made up in flat form of any specified length and utilized in that condition for equipment having flat walls or alternatively be quickly bent by hand into a shape to accommodate a curved wall. The structure provides a flexibility which enables the support to be bent into concave or convex curves of widely varying radii and arcs.

Among the important advantages of the flexibility characteristic is that it is conducive to sophisticated equipment design. For example, the wall of the heating unit can be contoured in a manner most expeditious to orienting the heating elements for maximum efficiency, or to accommodate unusual sizes or shapes of products or test speciments to be heated. The design need not be restricted to accommodate predetermined or standard shapes of supports. Having a wide range of flexibility, the support easily accommodates itself to the design of the equipment.

Furthermore, there is the advantage that manufacturing involves the production of a single kind of support unit usable either in a curved or planar form with consequent savings in tooling, labor and inventory costs.

A further advantage of the structure of the invention is that it can be manufactured using conventional tooling and techniques. The support utilizes strip stock which is easily formed into the desired shape. This is conducive to a support which is low in cost even though it has a wide versatility as mentioned above.

Another principal objective of the invention is to provide a support which has high strength under heat. The support is made of relatively thin strip stock configured into a shape which takes advantage of the expansion characteristics of metal under heat in a manner to effect a rigidity which makes the support as strong, or if not stronger, than at room conditions. The rigidity prevents undesirable sagging or expansion of the support under heat.

This rigidity characteristic of the invention is especially advantageous. It fulfills a prime requirement of equipment of the kind in question, namely, that the refractory blocks hold the electrical heating elements firmly and positively in position.

The preferred form of the invention will be described below in connection with the following drawings, wherein:

FIGURE 1 is an exploded view of supports of the invention arranged in concave form and supporting a refractory block-heating element assembly;

FIGURE 2 is a fragmentary, sectional view taken along the line 22 of FIGURE 1 and showing the support with a refractory block mounted thereon; and

FIGURE 3 is a reduced, fragmentary, plan view of a support of the kind shown in FIGURE 1 arranged in straight or planar form.

In FIGURE 1, I have shown a pair of identical sup ports 1 and 2 respectively mounting the refractory blocks 4 and 5, between which extend electrical heating elements indicated by the dot and dash lines 6. The heating elements 6 are preferably of the type shown in the Fisher Patent 2,856,496 assigned to the assignee of this invention.

For purposes of clarity, I have not shown a wall in FIGURE 1. However, it will be understood by those skilled in the art that the supports 1 and 2 are fastened directly to the refractory bricks or metal casing making up the wall, or alternatively, are fastened to a frame which is mounted on the wall. It will be understood, of course, that the supports are mountable on horizontal surfaces such as on a shelf or on the bottom or the top of heating equipment.

The supports 1 and 2 are identical in construction and the description will be made in connection with the support 1.

The support 1 includes metal strips 10 and 11. The strip 10 has integral leg and foot sections 12 .and 13. The strip 11 has integral leg and foot sections 14 and 15. As indicated, the respective leg and foot sections are arranged in the form of an L.

A lip section 15 on the strip 10 extends transversely of the foot section 13. The strip 11 has a lip 17 which extends transversely of the foot section 15.

Preferably the leg sections 12 and 14 lie in a common (in this case, curved) plane and the lip sections 16 and 17 also lie in a common plane which is generally parallel to the plane containing the leg sections. The foot sections 13 and 15 are butted together back to back.

The strips 10 and 11 are held together by means in the form of spot welds such as the weld 18 which joins the two foot sections 13 and 15.

The disposition of the foot and lip sections form a T- shaped portion and it is this portion which is adapted to mount the refractory blocks. This is best indicated in FIGURE 2 where the T-shaped portion for the support 1 is indicated at 20. The refractory block 4 has a corresponding T-shaped slot 21 whichaccommodates the T 20. The channels 22 and 23 formed by the leg, foot and lip sections respectively accommodate the portions 24 and 25 of the block 4. With the structure described, the blocks can be conveniently slid along the support 1. Each refractory block is provided with channels 26 and 27 which are adapted to hold resistor elements as indicated in FIG- URE 1. The blocks are prevented from sliding off the support by forming a small tab on the end of each lip such as the tab 28. For descriptive purposes, I have shown the refractory blocks .as spaced away from the tabs. It will be understood that in practice, it is usual to provide a sufficient number of blocks so that the same extend along the support between the tabs.

The support 1 is provided with a slots such as the slots 30. As

plurality of spaced best indicated in FIGURE 3, these slots extend through the foot and lip sections of both of the strips. The slots 30 have a special significance because they cooperate with the leg sections 12 and 14 to make the strip 10 bendable or flexible.

For example, in FIGURE 1 it will be noted that the strip 1 has been bent in a concave fashion, i.e. so that the outer portions 31 and 32 of the walls of the slot are closer together than at the root of the slot.

The slots 30 are shown provided for the strip 1 to be bent into a large number of concave curves. By making the slots wider or by tapering the same, a greater number of concave curvatures can be obtained. The supports can be bent in the opposite direction or to form a convex shape or bent into compound curves so that the support has both concave and convex sections.

It is to be noted that the thickness of the leg sections is chosen to give maximum rigidity under heat but to provide a flexibility so that the strips can be bent by hand.

Also, the length of each refractory block is chosen to be compatible with the curvatures of the support so that the blocks can freely slide on the support.

The ability of the strips to be bent into a variety of shapes is of special advantage particularly from the manufacturing and design standpoints. With the present invention, the interior shape of the equipment is not limited in any way by the strips because the strips can be quickly bentto accommodate the particular design. Thus, strips of some convenient length can be made up for inventory and then taken out for use in a unit having straight wall or for use in a unit having an arcuate interior wall.

Another very useful advantage of the invention is that the structure becomes more rigid with heat. This is brought about by the fact that under heat the foot sections 13 and 15 tend to move back toward their original position; i.e., in the plane of the leg sections. The forces developed to cause this movement oppose each other so that the foot sections are more tightly engaged. This has the effect of making a very rigid T portion which cannot droop or otherwise move during high temperature conditions. The rigidity of the T portion also imparts further strength to the leg sections of'the unit. This is highly desirable because it eliminates any chance of refractory blocks being moved to a point where the resistor elements might be dislodged or radically changed in position.

A very practical advantage of the invention is that contaminated or damaged refractory blocks can be easily replaced without removing the support from the wall or from its mounting frame. To replace a block, a tab is simply bent back into line and the blocks slid off the support until the damaged block is free. A new block is subtituted and the blocks are slid back on the support.

I claim:

1. A support for refractory blocks comprising: a pair of meal strips each having integral leg and foot sections, the strips being butted together with the respective leg sections lying in a common plane and with the respective foot sections engaging one another and means fixedly connecting the strips together.

2. A support'for refractory blocks comprising: a pair of metalstrips each having integral leg and foot sections with a lip section extending transversely of the foot section, the strips being butted together with the respective leg sections lying in a common plane and with the respective foot sections engaging one another and means fixedly connecting the strips together.

3. A support for refractory blocks comprising: a pair of metal strips each having integral leg and foot sections oriented in the form of an L with a lip section extending transversely the foot section, the strips being butted together with the respective leg sections lying in a common plane and the respective foot sections engaging one another and withlthe lip sections lying in a common plane and means fixedly connecting the strips together.

4. A construction in accordange with claim 3 wherein said means corn-prises spot welds welding the foot sections together.

5. A support for refractory blocks comprising: a pair of elongated metal strips each having integral leg and foot sections, the strips being butted together with the respective leg sections lying in a common plane and with the respective foot sections engaging one another and the foot sections being formed with a plurality of slots spaced from one another along the axis of the strip and means fixedly connecting the strips together, said leg sections and said slots cooperating to provide for bending the leg sections to make said common plane arcuate, planar, or both.

6. A support for refractory blocks comprising: a pair of metal strips each having integral leg and foot sections with a lip section extending transversely of the foot section, the strips being butted togetherwith the respective leg sections lying in a common plane and with the respective foot sections engaging one another and the leg and foot sections being formed with a plurality of slots spaced from one another along the axis oflthe strip and means fixedly connecting the strips together, said leg sections and said slots cooperating to provide for bending the leg sections to-make said common plane arcuate, planar, or both.

7. A support for refractory blocks comprising: a pair of metal strips each having integral leg and foot sections oriented in the form of an L with a ,lip section extending transversely the foot section, the strips being butted together with the respective leg sections lying in a common plane and the respective foot sections engaging one another and with the lip sections lying in a common plane and the lip and foot sections being formed with a plurality of slots spaced from one another along the axis of the strip and means fixedly connecting the strips together, said leg sections and said slots cooperating to provide for bending the leg sections to, make said common plane arcuate, planar, or both.

8. A construction in accordance with claim 7 wherein said means com-prises spot welds welding the foot sections together.

References Cited.

UNITED STATES PATENTS,

1,278,085 9/1918 Allmand 29193 3,071,855 1/1963 Mineah 29-183 3,238,779 3/1966 Wolfe 29-183 DAVID L. RECK, Primary Examiner.

RICHARD DEAN, Examiner. 

1. A SUPPORT FOR REFRACTORY BLOCKS COMPRISING: A PAIR OF MEAL STRIPS EACH HAVING INTEGRAL LEG AND FOOT SECTIONS, THE STRIPS BEING BUTTED TOGETHER WITH THE RESPECTIVE LEG SECTIONS LAYING IN A COMMON PLANE AND WITH THE RESPECTIVE FOOT SECTIONS ENGAGING ONE ANOTHER AND MEANS FIXEDLY CONNECTING THE STRIPS TOGETHER. 